(2x-3)(-x+5)-(x+3)(-4x+3) développé et reduire

(2x-) (-x+5)-(x+3)(-4x+3 :2x^2+10x+3x-15+4x^2-3x+12x-9 = 2x^2+22x-24 ; ^ = puissance. Bonne nuit.

Bonsoir,
(2x-3)(-x+5)-(x+3)(-4x+3)
=(2x*(-x)+2x*5 -3*(-x) -3*5) - ( x*(-4x) +x*3 +3*(-4x) +3*3)
=( -2x² +10x +3x -15) - ( -4x² +3x -12x + 9 )
= ( -2x² +13x -15)  - ( -4x² -9x +9)
= -2x² +13x -15 +4x² +9x -9
= ( -2x² +4x² ) +(13x +9x ) + ( -15 -9 )
= 2x² +22x -24.
Donc (2x-3)(-x+5) -(x+3)(-4x+3) = 2x² +22x -24.